According to Phonescoop, the Droid Incredible 2 operates on the following frequencies:
CDMA 850 / 1900
GSM 850 / 900 / 1800 / 1900
WCDMA 900 / 2100
The Motorola Atrix, which is available from AT&T, operates on the following frequencies:
GSM 850 / 900 / 1800 / 1900
WCDMA 850 / 1900 / 2100
And the HTC Inspire, which is also available from AT&T, operates on:
GSM 850 / 900 / 1800 / 1900
WCDMA 850 / 1900
GSM, I believe, is the voice channel, so that would mean that voice calls would work. However, I believe that WCDMA is for data, so that would lead one to believe that data would not work.
Someone can correct me if I got my frequencies and usage mixed up.